The background description provided herein is for the purpose of generally presenting the context of the present invention and is neither expressly nor impliedly admitted as prior art against the present invention. The subject matter discussed in the background of the invention section should not be assumed to be prior art merely as a result of its mention in the background of the invention section. Similarly, a problem mentioned in the background of the invention section or associated with the subject matter of the background of the invention section should not be assumed to have been previously recognized in the prior art. The subject matter in the background of the invention section merely represents different approaches, which in and of themselves may also be inventions.
The gearbox of a granulator is generally casted and molded by ASTM A45 30B class gray cast iron. The casting of the gearbox has four side walls, a top ceiling, and a bottom floor. Outer mounting feet are located at the bottom floor of the gearbox. The front side and the rear side of the gearbox are installed with cast hubs for supporting bearings for a gear shaft. Each of the left side and the right side of the gearbox is opened with an open portion, providing operation convenience for removal and inspection of the gear shaft. The side walls, the top ceiling, the bottom floor, and the cast hubs of the gearbox are all formed with ribs to enhance the rigidity and the strength of the gearbox. The gray cast iron material has excellent vibration dampening properties, and good strength for supporting the bearing and the gear shaft. Further, the manufacturing cost of the gray cast iron gearbox is low.
The hinge type pellet chamber in the related art is directly installed on the front end of the gearbox (ring die area). Installation plates are disposed in the corners of the front side wall of the gearbox. The installation plates have multiple connectors for connecting the hinge and the clamp. The hinge and the clamp are used for fixing the pellet chamber. The pellet chamber may be very heavy, thus cause a high stress on the installation plates of the casting. Under normal granulating condition, the gearbox can bear the concentrated stress; when over loaded, the pellet chamber may slide down. The most often incurred overload condition is that when a granulating mould is broken off, the loose parts after breaking off fall down and bump to the pellet chamber from the inside. Thus the pellet chamber applies a larger pressure on the installation plates, and subsequently the installation plates applies a larger pressure to one local area or a local point of the gearbox, which easily resulting in break-off of the gearbox at the connecting portion of the installation plate, or the installation plates break due to the high stress.
Therefore, a heretofore unaddressed need exists in the art to address the aforementioned deficiencies and inadequacies.